Journal of Geophysical Research: Biogeosciences最新文献_第3页

Nitrogen Processes Within Tropical Mangroves in Australia

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-27 DOI: 10.1029/2024JG008335

M. F. Adame, N. Iram, J. N. Gamboa-Cutz, P. Masque

{"title":"Nitrogen Processes Within Tropical Mangroves in Australia","authors":"M. F. Adame, N. Iram, J. N. Gamboa-Cutz, P. Masque","doi":"10.1029/2024JG008335","DOIUrl":"https://doi.org/10.1029/2024JG008335","url":null,"abstract":"Coastal wetlands have long been identified as ecosystems that can ameliorate N inputs into the ocean. The processes associated with N uptake, transformation, and losses are relatively well understood for temperate wetlands; however, information on tropical wetlands is scarce. In this study, we conducted a whole ecosystem approach to measure N processes within tropical mangroves in the Moresby estuary in northeast Australia. We measured N stocks (trees and soils), inputs from sedimentation, fixation, and accumulation as woody biomass, and outputs through denitrification, anammox, and soil respiration (N2O emissions). Potential denitrification was detected along anammox (average, min-max) at 883 (485–1,450) gN ha−1 day−1, followed by sediment accumulation with 108 (0–375) gN ha−1 day−1, and tree uptake with 93 (13–153) gN ha−1 day−1. Lower rates were found for N fixation with 45 (0–260) gN ha−1 day−1 and soil respiration as N2O with uptakes of −0.36 (−2.7 – 0.40) gN ha−1 day−1. Overall, mangroves in the Moresby estuary are fixing some N in their standing litter while removing NO3 and NH4+ from the water column through denitrification and anammox, temporarily storing N as woody biomass, and accumulating particulate N in their sediments. These mangroves are also functioning as sinks of N2O. Thus, the protection and restoration of these mangroves provide water quality and climate benefits.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008335","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143707494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessing the Molecular-Level Controls of Dissolved Organic Matter Cycling in West Siberian Lowland Rivers

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-27 DOI: 10.1029/2024JG008537

Martin R. Kurek, Oleg S. Pokrovsky, Ivan V. Krickov, Artem G. Lim, Mikhail А. Korets, Robert G. M. Spencer

{"title":"Assessing the Molecular-Level Controls of Dissolved Organic Matter Cycling in West Siberian Lowland Rivers","authors":"Martin R. Kurek, Oleg S. Pokrovsky, Ivan V. Krickov, Artem G. Lim, Mikhail А. Korets, Robert G. M. Spencer","doi":"10.1029/2024JG008537","DOIUrl":"https://doi.org/10.1029/2024JG008537","url":null,"abstract":"The West Siberian Lowland (WSL) contains some of the largest wetlands and most extensive peatlands on Earth, storing vast amounts of vulnerable carbon across permafrost-free to continuous permafrost zones. As temperature and precipitation changes continue to alter the Siberian landscape, carbon transfer to the atmosphere and export to the Arctic Ocean will be impacted. However, the drivers of organic carbon transfer are largely unknown across this region. We characterized seasonal dissolved organic carbon (DOC) concentration and dissolved organic matter (DOM) composition of WSL rivers from the middle reaches of the Ob’ River in the permafrost-free zone, as well as tributaries of the Taz River in the northern continuous permafrost zone. DOC and aromatic DOM properties increased from spring to autumn in the Ob’ tributaries, reflecting the seasonal transition from groundwater-sourced to terrestrial DOM. Differences in molecular-level signatures via ultra-high resolution mass spectrometry revealed the influence of redox processes on DOM composition in the winter while terrestrial DOM sourcing shifted from surface litter aliphatics and highly unsaturated and phenolic high-O/C (HUPHigh O/C) compounds in the spring to subsurface soils and HUPLow O/C compounds by autumn. Furthermore, aromaticity and organic N were related to landscape properties including peatlands, forest cover, and the ratio of needleleaf:broadleaf forests. Finally, the Taz River tributaries were similar to summer and autumn Ob’ tributaries, but more enriched in N and S-containing compounds. These signatures were likely derived from thawing permafrost, which we expect to increase in northern rivers due to active layer expansion in a warming Arctic.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143717253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Changes in Aquatic Carbon Following Rewetting of a Nutrient-Poor Northern Peatland

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-27 DOI: 10.1029/2024JG008565

Alberto Zannella, Karin Eklöf, Eliza Maher Hasselquist, Hjalmar Laudon, Mark H. Garnett, Marcus B. Wallin

{"title":"Changes in Aquatic Carbon Following Rewetting of a Nutrient-Poor Northern Peatland","authors":"Alberto Zannella, Karin Eklöf, Eliza Maher Hasselquist, Hjalmar Laudon, Mark H. Garnett, Marcus B. Wallin","doi":"10.1029/2024JG008565","DOIUrl":"https://doi.org/10.1029/2024JG008565","url":null,"abstract":"Rewetting drained peatlands by raising the groundwater table is currently suggested, and widely implemented, as an efficient measure to reduce peat soil degradation and decrease CO2 emissions. However, limited information exists regarding effects of peatland rewetting on lateral carbon export (LCE) via the aquatic pathway. Any changes in LCE are critical to consider, as they affect the overall peatland C balance, and may offset any climatic benefits from rewetting. Additionally, altered LCE could have consequences for downstream water quality and biota. Here, we monitored aquatic C content (DOC, DIC and CH4) in runoff and pore water, as well as radiocarbon content of DOC in runoff from a drained, nutrient-poor boreal peatland that was rewetted during autumn 2020. By comparing pre- (2019–2020) and post- (2021–2022) rewetting periods, we detected changes in the aquatic C export. The results showed that the rewetting effect was site-, season- and C form-specific. Overall, one catchment showed elevated (DOC, DIC) or highly elevated (CH4) concentrations and exports post-rewetting, whereas the other site showed only elevated DOC. Changes in runoff C concentrations after rewetting were likely driven by site-specific factors such as expansion of open-water areas, altered hydrological flow paths and proportion of filled in ditches of total ditch length. Finally, radiocarbon measurements indicated enhanced export of contemporary DOC via runoff following rewetting. These initial (short-term) findings highlight the need for site-specific before-after assessments to better evaluate the C sequestration capacity of peatlands while undergoing rewetting operations.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008565","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143717254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nitrate Loads and Concentrations From Forested Watersheds and Implications for Long Island Sound

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-27 DOI: 10.1029/2024JG008489

Alana B. Spaetzel, James B. Shanley, Leslie A. DeSimone, John R. Mullaney

{"title":"Nitrate Loads and Concentrations From Forested Watersheds and Implications for Long Island Sound","authors":"Alana B. Spaetzel, James B. Shanley, Leslie A. DeSimone, John R. Mullaney","doi":"10.1029/2024JG008489","DOIUrl":"https://doi.org/10.1029/2024JG008489","url":null,"abstract":"Reduction in point sources of nitrogen has led to improvement in water quality of the Long Island Sound (LIS) since 2000, but changes in nonpoint sources are less clear. A significant yet poorly quantified nonpoint nitrogen source is the forested landscape. Because a large proportion of the LIS basin is forested, even small areal inputs from the forested landscape have a large cumulative effect on nitrogen loading to LIS. Atmospheric nitrogen deposition, the primary source of nitrogen to forested landscapes in LIS basin, has been declining for several decades. However, nitrogen export in streams does not necessarily mirror nitrogen deposition. To assess forest nitrogen export to LIS, we estimated annual average concentrations and fluxes of nitrate in 17 forested watersheds in and near the LIS basin. Average flow-normalized nitrate-nitrogen concentrations ranged from less than 0.05–0.43 mg per liter among all sites; annual flow-normalized yields ranged from 0.45 to 4.3 kg per hectare. Flow-normalized annual average concentrations and yields of nitrate between water years 1991–2021 did not monotonically increase or decrease at most watersheds. Where determined, the other major N species generally had comparable magnitude and trends. Based on the watersheds analyzed in this study, forested areas are not responding uniformly to the continued decline of atmospheric nitrogen deposition. The variability among sites may indicate that local-scale factors exert substantial influence over the magnitude and trends in nitrogen exports. One watershed that had increasing development showed an increasing trend in nitrate, but not in dissolved organic nitrogen.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008489","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143717252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigating Spatial and Temporal Nitrogen Dynamics in a Forested Headwater Stream Over the Course of an Annual Drying Event

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-27 DOI: 10.1029/2024JG008522

Kaci Zarek, C. Nathan Jones, Delaney M. Peterson, Stephen Plont, Arial J. Shogren, Corianne Tatariw, Shannon L. Speir, Behzad Mortazavi, Amy J. Burgin

{"title":"Investigating Spatial and Temporal Nitrogen Dynamics in a Forested Headwater Stream Over the Course of an Annual Drying Event","authors":"Kaci Zarek, C. Nathan Jones, Delaney M. Peterson, Stephen Plont, Arial J. Shogren, Corianne Tatariw, Shannon L. Speir, Behzad Mortazavi, Amy J. Burgin","doi":"10.1029/2024JG008522","DOIUrl":"https://doi.org/10.1029/2024JG008522","url":null,"abstract":"Headwater streams make up nearly 80% of the stream network by length and play an important role in shaping the physical, chemical, and biological functions of downstream waters. In the Southeastern US, these systems are beginning to experience increases in the frequency and duration of drying, but it is unclear how increased drying will impact downstream water quality. To begin to address this issue, we examined nitrogen dynamics in a forested headwater stream across an annual drying event. The annual drying event was divided into seasonal wet (March–June), dry-down (June–October), and rewet (November–March) periods. We used a combination of water quality sensors at the watershed outlet, spatially distributed synoptic sampling of net denitrification conditions and physicochemical variables across the watershed, and a series of denitrification potential experiments to examine variation in biogeochemical state across the annual drying event. At the watershed outlet, nitrate concentrations were positively correlated with increased watershed-scale connectivity during the rewet period, while nitrate concentrations were positively correlated with increased streamflow during the dry-down period. Throughout the watershed, net denitrification conditions varied more across seasons than space, with greater net denitrification conditions during the dry-down period. Further, net denitrification conditions were positively correlated to stream temperature, nitrate, and ammonium concentrations but inversely related to streamflow. Finally, denitrification measurements confirmed the dry-down period experienced the highest denitrification rates. Our results highlight the connection between stream drying and nitrogen dynamics in humid systems, providing key information for developing predictive understanding of headwater streams.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143707496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Seasonally Dynamic Dissolved Carbon Cycling in a Large Hard Water Lake 大型硬水湖中的季节性动态溶解碳循环

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-22 DOI: 10.1029/2024JG008645

Margot E. White, Benedict V. A. Mittelbach, Nicolas Escoffier, Timo M. Y. Rhyner, Negar Haghipour, David J. Janssen, Marie-Elodie Perga, Nathalie Dubois, Timothy I. Eglinton

{"title":"Seasonally Dynamic Dissolved Carbon Cycling in a Large Hard Water Lake","authors":"Margot E. White, Benedict V. A. Mittelbach, Nicolas Escoffier, Timo M. Y. Rhyner, Negar Haghipour, David J. Janssen, Marie-Elodie Perga, Nathalie Dubois, Timothy I. Eglinton","doi":"10.1029/2024JG008645","DOIUrl":"https://doi.org/10.1029/2024JG008645","url":null,"abstract":"Inland waters play a crucial role in the global carbon cycle, with lakes integrating carbon from various sources within their catchment in addition to that fixed by local primary productivity. Isotopic measurements of carbon pools can differentiate contributions from these sources, with natural abundance radiocarbon (14C) a particularly powerful tool due to the large range in 14C characteristics among carbon sources. Here, we present 14C measurements of dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC) from monthly water column samplings over the course of a year in Lake Geneva, a large oligotrophic hard water perialpine lake in Western Europe. We find that DIC in the lake is significantly 14C-depleted relative to the atmosphere primarily due to the dissolution of carbonate rocks in the lake's catchment. Variability in DI14C is largely tied to the Rhône River inflow, where DI14C values were also found to vary seasonally. DOC has a 14C signature similar to that of DIC, reflecting the fact that much of the lake DOC pool is autochthonous. However, more 14C-depleted DOC was observed in July and tied to increased river discharge from snow and glacier melt within the upper Rhône River basin. These observations shed light on carbon sources and dynamics within Lake Geneva and its alpine catchment and highlight the importance of preaged dissolved carbon inputs to the largest natural lake in Western Europe.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 3","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008645","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143689431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Soil Net N Mineralization Potential and Its Temperature Sensitivity Along a North-South Forest Transect in the Eastern China

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-22 DOI: 10.1029/2024JG008672

Shuya Hu, Changhui Wang, Nianpeng He, Ang Li, Yingliu Wang, Xingguo Han, Jianhui Huang

{"title":"Soil Net N Mineralization Potential and Its Temperature Sensitivity Along a North-South Forest Transect in the Eastern China","authors":"Shuya Hu, Changhui Wang, Nianpeng He, Ang Li, Yingliu Wang, Xingguo Han, Jianhui Huang","doi":"10.1029/2024JG008672","DOIUrl":"https://doi.org/10.1029/2024JG008672","url":null,"abstract":"Soil net nitrogen (N) mineralization potential (Rmin) is a key indicator for predicting the capacity of available N supply for plant growth and ecosystem productivity. Thus, it is crucial to understand the spatial pattern and regulatory mechanisms of forest Rmin and its temperature sensitivity (Q10) under current global change scenarios. In this study, we determined the Rmin and its Q10 value of soil samples collected from 18 forest ecosystems along a 5200-km-long north-south forest transect in eastern China. We found significant differences in Rmin and its Q10 values among different forest types. Tropical and subtropical forests had significantly higher Rmin values than temperate forests and cold temperate forests. In contrast, tropical and subtropical forests had the lowest Q10 values followed by temperate forests and cold temperate forests. Rmin varied with mean annual precipitation, soil total carbon (C) and N, microbial biomass carbon (MBC) and the MBC to the microbial biomass nitrogen (MBN) ratio. The Q10 value varied with the mean annual temperature (MAT), the MBC/MBN ratio, and aridity index. Overall, our results indicate that the Q10 value of the Rmin is generally lower in warmer or wetter areas than in colder or drier areas along the north-south forest transect in eastern China. Our results imply that the predicted global change may narrow the gaps in the Rmin between high- and low-latitude forests or among forests with different humidity levels.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 3","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143689432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Morphology and Distribution of Bubble-Supported Microbial Mats From Ice-Covered Antarctic Lakes

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-21 DOI: 10.1029/2024JG008516

M. Juarez Rivera, T. J. Mackey, I. Hawes, D. Y. Sumner

{"title":"Morphology and Distribution of Bubble-Supported Microbial Mats From Ice-Covered Antarctic Lakes","authors":"M. Juarez Rivera, T. J. Mackey, I. Hawes, D. Y. Sumner","doi":"10.1029/2024JG008516","DOIUrl":"https://doi.org/10.1029/2024JG008516","url":null,"abstract":"Gas bubbles directly influence the macromorphology of benthic microbial mats resulting in preservable biosedimentary structures. This study characterizes the morphology and distribution of microbial mats growing in gas-supersaturated, perennially ice-covered lakes Fryxell, Joyce, and Hoare of the McMurdo Dry Valleys of Antarctica. Photosynthetic benthic mats within the gas-supersaturated zone trap oxygen-rich bubbles and become buoyant, tearing off the bottom as “liftoff mats.” These liftoff mats form a succession of morphologies starting with bubble-induced deformation of flat mats into tent, ridge, and finger liftoff mat. With progressive deformation, mats tear, forming sheet liftoff, while multiple cycles of deformation and tearing transform sheet into strip liftoff. Some mats detach from the substrate and float to the underside of the ice. The depth range of the liftoff zone has varied over time at each lake. Downslope expansion of bubble formation brings previously bubble-free, deep-water pinnacle mats into the liftoff zone. When the liftoff zone shallows, liftoff mats at the deeper end deflate and can become scaffolding for additional mat growth. The superposition and relative orientation of liftoff and pinnacle mats can be used to track the maximum depth of the liftoff zone and changes in gas saturation state in these lakes through time. Our results demonstrate that gas bubbles, even when they are transitory, can exert a significant impact on the morphology of microbial mats at larger scales. This provides a way to identify similar structures and gas supersaturated environments in the biosedimentary record.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 3","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008516","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143689522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Changes in the Factors Influencing Forest Floor Terpenoid Emissions During Post-Fire Forest Succession

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-21 DOI: 10.1029/2024JG008113

Huizhong Zhang-Turpeinen, Heidi Aaltonen, Jing Tang, Dan Kou, Minna Kivimäenpää, Riikka Rinnan, Jukka Pumpanen

{"title":"Changes in the Factors Influencing Forest Floor Terpenoid Emissions During Post-Fire Forest Succession","authors":"Huizhong Zhang-Turpeinen, Heidi Aaltonen, Jing Tang, Dan Kou, Minna Kivimäenpää, Riikka Rinnan, Jukka Pumpanen","doi":"10.1029/2024JG008113","DOIUrl":"https://doi.org/10.1029/2024JG008113","url":null,"abstract":"The forest floor acts as a source of terpenoid emissions to the atmosphere. These emissions can further impact atmospheric particle formation and impact the atmospheric radiation balance. Climate change escalates wildfire frequency in boreal forests. Wildfires are major disturbances with long-term ecosystem impacts, particularly on the forest floor, significantly influencing terpenoid sources and emissions. This study quantified the post-fire terpenoid emissions from the forest floor and characterized micro-environmental conditions, including abiotic (e.g., air temperature, soil temperature, soil moisture, and light intensity) and biotic factors (ground vegetation characteristics, soil respiration (CO2 fluxes), and soil microbial biomass). We aimed to understand how abiotic and biotic factors affect terpenoid emissions during post-fire succession. Path models revealed direct impacts of ground vegetation on isoprene and monoterpene emissions, while sesquiterpene emissions were mainly regulated by various abiotic factors. Isoprene and monoterpene emissions were influenced by both direct and indirect abiotic factors, mediated through biotic factors like vegetation and soil processes. Effect sizes of the influencing factors varied across forest age classes. Due to the post-fire regrowth of ground vegetation, the impact of temperature on emissions was more pronounced in earlier burned areas than recently burned areas. The influence of soil moisture on terpenoid emissions diminished with forest age. Our findings emphasize the need to identify factors influencing forest floor terpenoid emissions across post-fire succession stages to understand and predict their emission patterns and subsequent impacts on climate.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 3","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143689530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Allometric Scaling of Hyporheic Respiration Across Basins in the Pacific Northwest United States

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-20 DOI: 10.1029/2024JG008344

P. Regier, K. Son, X. Chen, Y. Fang, P. Jiang, M. Taylor, W. M. Wollheim, J. Stegen

{"title":"Allometric Scaling of Hyporheic Respiration Across Basins in the Pacific Northwest United States","authors":"P. Regier, K. Son, X. Chen, Y. Fang, P. Jiang, M. Taylor, W. M. Wollheim, J. Stegen","doi":"10.1029/2024JG008344","DOIUrl":"https://doi.org/10.1029/2024JG008344","url":null,"abstract":"Hyporheic zones regulate biogeochemical processes in streams and rivers, but high spatiotemporal heterogeneity makes it difficult to predict how these processes scale from individual reaches to river basins. Recent work applying allometric scaling (i.e., power-law relationships between size and function) to river networks provides a new paradigm for understanding cumulative hyporheic biogeochemical processes. We used previously published model predictions of reach-scale hyporheic aerobic respiration to explore patterns in allometric scaling across two climatically divergent basins with differing characteristics in the Pacific Northwest, United States. In the model, hydrologic exchange fluxes (HEFs) regulate hyporheic respiration, so we examined how HEFs might influence allometric scaling of respiration. We found consistent scaling behaviors where HEFs were either very low or very high, but differences between basins when HEFs were moderate. Our findings provide initial model-generated hypotheses for factors influencing allometric scaling of hyporheic respiration. These hypotheses can be used to optimize new data generation efforts aimed at developing predictive understanding of allometries that can, in turn, be used to scale biogeochemical dynamics across watersheds.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 3","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008344","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0